Pump for high viscosity fluids



Oct. 20, 1964 Filed Jan. 17, 1963 R. LE Emmi BOWEN, JR 3,153,385

PUMP FOR HIGH VISCOSITY FLUIDS 3 Sheets-Sheet 1 IN V EN TOR.

RICHARD LEBARON BOWEN,JR.

ATTORNEYS Oct. 20, '1964 R. LE BARQN BOWEN, JR

PUMP FOR HIGH VISCOSITY FLUIDS Fil ed Jan. 17, 1963 3 Sheets-Sheet 2INVENTOR. RICHARD LEBARON BOWEN, JR.

R. LE BARGN raowEN, JR 3,153,385

PUMP FOR HIGH VISCOSITY mums 3 Sheets-Sheet IS Filed Jan. 17, 1963INVENTOR. F l G '5 RICHARD LEBARON BOWEN, JR

ATTORNEYS United States Patent 3,153,3ss PUMP FGR HIGH VISCIISITY FLUIDSRichard Le Baron Bowen, In, 35 Fessenden Road, Barrington, RI. FiledIan. 17, 1963, Ser. No. 252,550 16 Claims. (Cl. 103-153) This inventionrelates to piston pumps, and more particularly to those of the meteringtype for handling fluids of a viscous nature, such as pastes, slurries,plastic fluids, heavy oils, grease and the like and is acontinuation-inpart of my application, Serial No. 37,643 filed June 21,1960, now abandoned.

The primary object of this invention is to provide a pump for handlingviscous fluids which is of positive displacement so that it can be usedfor metering service which requires that the rate of pumping bemaintained precisely.

Previously piston pumps for this type of service have suffered from thefact that there was leakage of fluid between the piston and/ or rod andthe pump body at the point where the piston and/or rod emerged from thepump body. Previous pumps of this type used conventional packing withpacking glands to solve this problem. However, pasty or plastic fluidstend to cling to the piston and/ or rod to such a degree that after anumber of strokes they cause any stationary packing to fail. Other materials with abrasive particles mechanically destroy the stationary typeof packing.

A more specific object of this invention is therefore to provide a pumpin which no packing or packing gland is used.

A further object is to provide a pump with a .permanently sealed pistonwhich can be used to handle pasty or plastic fluids.

Also an object of the invention is a simple and highly eflicient pumpfor handling very viscous materials with out the problem of leakage.

Additional objects and advantages will become apparent in the followingdescription and claims.

Referring to the drawings wherein like reference characters refer tolike parts:

FIGURE 1 is a side elevation of one design of the pump shown partly insection wherein the piston is shown midway of the discharge stroke;

FIGURE 2 shows a side elevation partly in section of a pump with analternate piston for the pump body as shown in FIGURE 1;

FIGURE 3 is a side elevation partly in section of the piston of FIGURE1;

FIGURE 4 is a sectional view taken along lines 44 of FIGURE 3;

FIGURE 5 shows an alternate configuration of the pump body of FIGURE 1;

FIGURE 6 shows an alternative method of providing a sealed connection inthe configuration of FIG. 2;

FIGURE 7 shows an alternative configuration of the pump body. shown inFIGURES 1 and 2;

FIGURE 8 shows another alternative configuration of the pump body shownin FIGURES 1 and 2;

FIGURE 9 shows an alternative arrangement of a piston for the pump shownin FIGURE 8;

FIGURE 10 shows an end view of the piston of FIG- URE 9;

FIGURE 11 shows another alternative arrangement of the piston shown inFIGURE 8;

FIGURE 12 shows an end view of the piston of FIG- URE 11; and

FIGURES 13-15 show further alternate pump configurations.

Referring now to the drawings, FIGURE 1 shows a ice pump having a body15 with a suction opening 16 and discharge opening 17. Adjacent thedischarge opening 17 is a ball check valve 18 that is urged toward aseat at the discharge opening 17 by a spring 19 held in a housing 20that is fastened to the pump body 15. This ball valve 18 is guided byvanes 21 which yield sufficient area therebetween to allow the passageof fluid thereby and on to the outlet 22.

The pump body 15 is provided with a bore 23 in which is slidablyreceived a piston 24 that is connected by means of a link 25 to a primemover shaft 26 through an eccentric 27. It will be evident that rotationof the shaft 26 causes the piston 24 to reciprocate in bore 23. Thepiston 24 is encircled after it emerges from the pump body 15 by aflexible bellows 28 which has one end aflixed to the pump body as at 29by a ring 30 while the other end is fastened by means of a second ring31 affixed to the end of the piston 24. Accordingly, as the pistonreciprocates, it will be apparent that the bellows will expand andcontract. It is evident that as the bellows expands upon retraction ofthe piston from the bore that the volume within the bellows willincrease, the converse being true as the piston moves in the otherdirection or to the right as viewed in the drawing. Since leakage occursalong the extent the piston, it is evident that upon the reduction involume of the bellows, a pressure will be generated within the bellowsunless some means is provided to eliminate this pressure that would intime cause a rupture of the bellows. Means are provided to connect thebellows area with the suction opening. This means consists of a passage36 formed between the suction 16 towards the bellows seal area inconjunction with a longitudinal recess 37 cut into the piston. Thesepassageways 36 and 37 communicate with each other and with the interiorof the area within the bellows so that the pressure within the bellowswill be kept to a minimum and certainly not exceeding that on thesuction of the pump. This then keeps the seal around the pump at aminimum pressure which will increase the life of the bellows since thislife is a direct function of the pressure under which the bellowsoperates whether the bellows is made of metal or of non-metallicmaterials.

Referring now to FIGS. 3 and 4, the specific arrange ment of the piston24 is brought out more fully wherein I the slot 37 is shown as being cutlongitudinally into the periphery of the piston, this slot beingsufliciently long so that communication will be had at all times betweenthe bellows and the suction at both ends of the stroke.

Referring now to FIG. 2, there is shownhere another form of a pump inwhich the piston 24' is provided with a reduced section or piston rod 40that connects the piston 24 with the connecting link means 25. In theshowing in FIG. 2 the piston is shown as nearly in its fully retractedposition, and it will be noted that the passage 36 still has not beencompletely covered up by the retraction of the piston 24' nor will it atany time be completely covered. When the piston proceeds to the right asviewed in'the drawing to the discharge position which is shown in brokenlines, the diameter of the piston rod 40 is such that communication willalways be had between the suction opening and the interior of thebellows 28 because of the relative diameter of the parts.

Under certain conditions it is not always necessary to provide a passage36 between the suction opening and the area towards the back side of thepiston. For instance, in referring to FIG. 5 I have shown a portion of apump body such as is disclosed in the preceding figures in which no suchpassageway is provided. In this case the reciprocation of the piston issuch that it is limited so that it does not completely go beyond thesuction opening. In this case merely the recess 37 and a piston 24 isnecessary 3 to provide the communication between the bellows 28 and thesuction opening 16.

Referring now to FIG. 6, there is shown an alternate means of providinga flexible connection between the piston and the pump body which couldbe used to replace the bellows shown in FIGS. 1 and 2. In FIG. 6 thepiston is shown in its retracted position in full lines and in brokenlines at the position at the end of the discharge stroke. The flexibleconnection in this embodiment con-. sists of a flexible connectorsupported by a sleeve 51 which is aflixed to the piston 52 by means of anut 53 on the piston rod 54. The flexible connector 5% extends down thesleeve 51 and rolls back as at 55 and is connected to the pump body 15by means of an external sleeve 57. As the piston 52 is moved to theright, the roll in the flexible connector also moves to the right and issupported by the external sleeve 5'7 and by the internal sleeve 51. Itis evident that the chamber formed between the end of the piston 52 andthe roll 55 around the connector 59 decreases as the piston 52 is movedto the left. Thus, fluid will pass through the passage 36 adjacent thesuction opening 36 when the piston moves to the far left.

In FIG. 7 there is shown an alternate arrangement consisting principallyof a different pump body. Here the pump body 15' is provided with aninlet 16, a bore 23 and a discharge opening 60. Here the dischargeopening is located to the side of the bore 23 rather than at the endthereof as in FIGS. 1, 2 and 6. As in the previous embodiments the checkvalve unit is quite similar and consists of the usual casing 20 with aball check 13 and a spring 19'. In this pump body 15' there is provideda piston 24' which is fitted for reciprocation in the bore 23 as in theprevious embodiments. A passageway 36' is also formed in this pump body15' adjacent the suction opening 16, and this permits equalization ofpressures as before, there being identical construction of the sealingdevice used in conjunction with this embodiment as has been shown inconnection with FIGS. 2 and 6.

FIG. 8 shows still another modification of the pump body together with amodification of the piston. Here we have a pump body 7-9 provided with asuction opening 71 opening into a bore 72 in which there is fitted forreciprocation a piston 73. A discharge port 74 is provided substantiallydiametrically opposite the suction opening 71 and has fitted thereto acheck valve body 20 as in the previous embodiments. The piston 73 isfabricated in an entirely different fashion and is provided with ageneral L-shape, there being a substantial cutout portion as at 75 whichopens towards the discharge opening 74). This cutout portion '75 isprovided so that fluid will pass out of the discharge opening 74 oncethe end '76 of the piston passes the suction opening 71 on the dischargestroke. Similarly in this case there is provided a passageway 7'7adjacent the suction opening '71 which will permit communication withthe bellows sealing the piston rod 7% much as has been done in theprevious showings in FIGS. 1, 2 and 6.

In FIGS. 9 to 12 there is illustrated some specific forms which thepiston 73 of FIG. 8 may take. For example, in FIG. 9 there is shown apiston 73 which is provided with a cutout portion 75 or passageway topermit the fluid being discharged to pass out of the discharge opening.This piston showing is much the same as that in FIG. 8 except less of acutout portion is utilized. In FIG. 11 still a further alternatearrangement has been illustrated where the piston 73" is provided with adefinite central bore 75" and a cutout portion 849 opening to one sideof this bore to permit fluid to pass to the discharge opening such as'74. The pistons '73 and '73 that have been illustrated are useful sincethey provide a greater contact area with the bore 72 and thereforepermit a greater sealing area between the discharge opening and thesuction. A still further advantage is inherent in the piston designshown in FIGS. 11 and 12 where a more properly hydraulically balancedpiston is provided.

FIGURE 13 illustrates another type of flexible sealing member which canbe used. Here We have a pump body 8% with suction opening '81 openinginto bore 82 in which is fitted for reciprocation a piston 83. A checkvalve body 29 is fitted to the discharge as before in the previousembodiments. At the back end of the pump body 84 is a flange 84 whichholds the outside edge of diaphragm 85 by means of ring 86. Diaphragm 85is fixed to piston 83 by means of washer 8'7 and nut 88. Operation ofthis modification is identical to the other embodiments.

- FIGURE 14 represents a further modification of FIGURE 13, wherein ring86 is replaced by cap 90 which is fitted with guide 91 for extension 92of piston 93, the cap 90 acting as a guard for the diaphragm.

FIGURE 15 represents a slight variation of FIGURE 14. Here the suctionopening 101 has been located at an extreme position adjacent theactuating end of the piston. In this arrangement, the suction port 193is a plurality of recesses axially oriented around the bore. The innerend of the suction opening as at 104 provides what in effect is apassageway between the opening and the area of variable volume formed bythe diaphragm 102. In all other respects this embodiment is equivalentto that shown in FIGURE 14.

I claim:

1. In a pump, a pump body, said body providing walls defining a bore, apiston fitted for reciprocation in said bore with a free end extendinginto said bore, means connected to the end of said piston opposite saidfree end for actuating said piston, a flexible member forming a sealedconnection between the end of said piston opposite said free end andsaid pump bore adjacent said actuating means, said flexible sealingconnection forming a chamber of variable volume, a discharge portconnecting with said bore, a suction port intermediate the chamber ofvariable volume and the discharge port, and means connecting saidsuction port and said chamber formed by the flexible sealing connection.

2. In a pump as in claim 1 wherein the means between the suction portand the chamber comprises a cutout portion of the wall of said boreopening at one end thereof into the suction port and at the other endinto the chamber of variable volume.

3. In a pump as in claim 1 wherein the means between the suction portand the chamber comprises a recess cut into the piston, said recessbeing of suflicient length to insure communication between the suctionport and the chamber at all times.

4. In a pump as in claim 1 wherein the means between the suction portand the chamber comprises a cutout portion of the wall of the boreopening at one end thereof into the suction port and at the other endinto the chamber, and also a recess .cut into the piston, said recessbeing of suflicient length to insure communication between the suctionport and the chamber at all times.

5. In a pump, a pump body, said body providing walls defining a bore, apiston fitted for reciprocation in said bore with a free end extendingto said bore, means connected to the end of said piston opposite saidfree end for actuating said piston, a flexible member forming a sealedconnection between the end of said piston opposite said free end andsaid pump bore adjacent said actuating means, said flexible sealingconnection forming a chamber of variable volume, a suction port openinginto said bore, said suction port being located so that said pistonseals said suction port off part way through the discharge stroke ofsaid piston, a discharge port connecting with said bore, and a meansconnecting said suction port and said chamber formed by the flexiblesealing connection.

6. In a pump as in claim 5 wherein the means between the suction portand the chamber comprises a cutout portion of the Wall of said boreopening at one end thereof into the suction port and at the other endinto the chamber of variable volume.

7. In a pump as in claim 5 wherein the means between the suction portand the chamber comprises a recess cut into the piston, said recessbeing of sufficient length to insure communication between the suctionport and the chamber at all times.

8. In a pump as in claim 5 wherein the means between the suction portand the chamber comprises a cutout portion of the wall of the boreopening at one end thereof into the suction port and at the other endinto the chamber, and also a recess cut into the piston, said recessbeing of sufficient length to insure communication between the suctionport and the chamber at all times.

9. In a pump, a pump body, said body providing walls defining a bore, apiston fitted for reciprocation in said bore with a free end extendinginto said bore, means connected to the end of said piston opposite saidfree end for actuating said piston, a flexible member forming a sealedconnection between the end of said piston opposite said free end andsaid pump bore adjacent said actuating means, said flexible sealingconnection forming a chamber of variable volume, a suction port openinginto said bore, saidsuction port being located so that at the end of thedischarge stroke of said piston said suction port is positioned betweenthe free end of said piston and the actuating means of said piston, adischarge port connecting with said bore, and a means connecting saidsuction port and said chamber formed by the flexible sealing connection.

10. In a pump as in .claim 9 wherein the means between the suction portand the chamber comprises a cutout portion of the wall of said boreopening at one end thereof into the suction port and at the other endinto the chamber of variable volume.

11. In a pump as in claim 9 wherein the means between the suction portand the chamber comprises a recess cut into the piston, said recessbeing of suflicient length to insure communication between the suctionport and the chamber at all times.

12. In a pump as in claim 9 wherein the means between the suction portand the chamber comprises a cutout portion of the wall of the boreopening at one end thereof into the suction opening and at the other endinto the chamber, and also a recess cut into the piston, said recessbeing of suflicient length to insure communication between the suctionport and the chamber at all times.

13. In a pump, a pump body, said body providing walls defining a bore, apiston fitted for reciprocation in said bore, means passing through saidbody for actuating said piston, a flexible member forming a sealedconnection between said piston and said body adjacent the actuatingmeans, said flexible sealing connection forming a chamber of variablevolume, a suction port opening into said bore, a discharge portconnecting with said bore, and a passageway means connecting saidsuction port and said chamber formed by the flexible sealing connection,said passageway means comprising a cutout portion of the Wall of saidbore opening at one end thereof into the suction port and at the otherend into the chamber of variable volume.

14. In a pump as in claim 13 wherein the suction port is located so thatat the end of the discharge stroke said suction port is position betweenthe end of the piston opposite the piston actuating means and theactuating means so that said suction port is effectively closed by saidpiston.

15. In a pump, a pump body, said body providing walls defining a bore, apiston fitted for reciprocation in said bore, means passing through saidbody for actuating said piston, a flexible member forming a sealedconnection between said piston and said body adjacent the actuatingmeans, said flexible sealing connection forming a chamber of variablevolume, a suction port opening into said bore, a'discharge portconnecting with said bore, and a passageway means connecting saidsuction port and said chamber formed by the flexible sealed connection,said passageway means comprising a recess cut into the piston, saidrecess being of sufficient length to insure communication between thesuction port and the chamber at all times.

16. In a pump as in claim 15 wherein the suction port is located so thatat the end of the discharge stroke said suction port is positionedbetween the end of the piston opposite the piston actuating means andthe actuating means so that said suction port is effectively closed bysaid piston.

References Cited in the file of this patent UNITED STATES PATENTS2,180,818 Fields et a1. Nov. 21, 1939

1. IN A PUMP, A PUMP BODY, SAID BODY PROVIDING WALLS DEFINING A BORE, APISTON FITTED FOR RECIPROCATION IN SAID BORE WITH A FREE END EXTENDINGINTO SAID BORE, MEANS CONNECTED TO THE END OF SAID PISTON OPPOSITE SAIDFREE END FOR ACTUATING SAID PISTON, A FLEXIBLE MEMBER FORMING A SEALEDCONNECTION BETWEEN THE END OF SAID PISTON OPPOSITE SAID FREE END ANDSAID PUMP BORE ADJACENT SAID ACTUATING MEANS, SAID FLEXIBLE SEALINGCONNECTION FORMING A CHAMBER OF VARIABLE VOLUME, A DISCHARGE PORTCONNECTING WITH SAID BORE, A SUCTION PORT INTERMEDIATE THE CHAMBER OFVARIABLE VOLUME AND THE DISCHARGE PORT, AND MEANS CONNECTING SAIDSUCTION PORT AND SAID CHAMBER FORMED BY THE FLEXIBLE SEALING CONNECTION.